Of the Trek series I’ve watched, I consider DS9 the only one that really managed to realize its full potential. TOS was hampered by its episodic nature and strict focus on Kirk/Spock/McCoy; TNG by awful technobabble and Roddenberry’s utopian crap; and TAS by cheap animation, short runtime, and some really dire voice acting on Doohan’s part. Aside from everything to do with Worf and the Klingons, I have no similar gripes with DS9.
The only part of the Klingon/Worf angle I was really disappointed by was Alexander’s return. They kinda turned him in to a wussy. I think they could have done his story with Worf and being a Klingon far better. Worf’s inclusion really did add a great element to an already great story. Some of the off the cuff humor alone between him, Jadzia, Bashir, and O’Brien was well worth the time they put in to it.